Seal

ABSTRACT

A seal for an opening in a treatment chamber through which material continuously enters and/or exits from the chamber. The seal includes an endless inflatable element which is fixed relative to the chamber wall and which extends around the periphery of the opening, and an intermediate member suspended in the opening in a stationary position completely surrounded by the inflatable element. In a typical arrangement where one opening serves as both the entrance and exit for the material being processed, the material entering the chamber passes between the inflatable element and one side of the intermediate member, and the material exiting from the chamber passes between the inflatable element and the opposite side of the intermediate member. The inflatable element is inflated to an extent such that the space between the intermediate member and the periphery of the opening is effectively sealed, with the material entering and leaving the chamber being sealingly engaged between the inflatable element and the intermediate member.

[is] 3,645,1l6

[ 1 Feb.29,i972

Elite tates tent Peter [54] SEAL [72] Inventor: Fritz Peter, Shrewsbury, Mass.

[73] Assignee: Rodney Hunt Company, Orange, Mass.

[22] Filed: Aug. 5, 1970 [21] Appl. No.: 61,455

Related US. Application Data Primary ExaminerWilliam i. Price Attorney-Chittick, Pfund, Birch, Samuels and Gauthier [5 7] ABSTRACT A seal for an opening in a treatment chamber through which material continuously enters and/or exits from the chamber. The seal includes an endless inflatable element which is fixed relative to the chamber wall and which extends around the periphery of the opening, and an intermediate member suspended in the opening in a stationary position completely surrounded by the inflatable element. In a typical arrangement where one opening serves as both the entrance and exit for the material being processed, the material entering the chamber passes between the inflatable element and one side of the intermediate member, and the material exiting from the chamber passes between the inflatable element and the opposite side of the intermediate member. The inflatable element is inflated to an extent such that the space between the intermediate member and the periphery of the opening is effectively sealed, with the material entering and leaving the chamber being sealingly engaged between the inflatable element and the intermediate member.

13 Claims, 5 Drawing Figures PATENTEDFEB29|912 SHEET 1 OF 3 lzweaainam- Fmwz l'eiez' a W M MM SEAL This is a continuation of application Ser. No. 800,963, filed Feb. 20, 1969, and now abandoned.

DESCRIPTION OF THE INVENTION This invention relates generally to sealing devices, and more particularly to a seal for an opening in a treatment chamber through which the material being processed may continuously enter and/or exit from the chamber.

The invention will hereinafter be described in connection with an apparatus for continuously processing open width material, such as for example a cloth web. However, it should be noted at the outset that reference to this particular type of operation is for illustrative purposes only, it being understood that the invention may also be employed in other areas where material is being continuously passed through a chamber, vessel or the like for treatment.

Known seal arrangements of the foregoing type have a number of problems associated therewith, problems which prior to the present invention, had never been solved 'to the complete satisfaction of those skilled in the art. For example, several prior art seal arrangements, such as those disclosed in US. Pat. Nos. 3,302,432, (Woollatt, et al.) and No. 3,343,379, (Duis, et al.) employ inflatable sealing elements, either in an opposed relationship or in combination with noninflatable stationary members, to sealingly engage the opposite sides of open width material passing therebetween. These inflatable elements extend coextensively with the side edges of the opening in the chamber wall, but not with the ends of the opening. Thus, although these arrangements provide an adequate seal across the width of the material entering and leaving the chamber, experience has indicated that the means employed to seal the ends of the chamber wall openings are complicated, difficult to assemble and in most instances, inadequate.

Accordingly, it is a primary object of the present invention to overcome the above-mentioned difficulties by providing an improved sealing arrangement which is effective along the entire periphery of the opening through which material enters and/or exits from the chamber.

A further object of the present invention is to provide an improved seal assembly which is comprised of a minimum number of components which can be easily and quickly assembled and disassembled when servicing the apparatus.

A still further object of the present invention is to increase the durability of the seal, thus minimizing the time and expense expended on maintenance.

These and other objects and advantages of the present invention will become more apparent as the description proceeds with the aid of the accompanying drawings in which:

FIG. I is a sectional view schematically depicting a treatment chamber having associated therewith one embodiment of a seal constructed in accordance with the present invention;

FIG. 2 is a plan view on an enlarged scale taken along lines 2-2 of FIG. 1;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a sectional view showing an alternate embodiment of the inflatable sealing element; and,

FIG. 5 is an illustration of the seal assembly employed to seal an opening through which material passes in only one direction.

Referring initially to FIG. I, a treatment chamber generally indicated by the reference numeral is shown comprising a cylindrical chamber wall 12 supported at floor lever on legs 14. The ends of cylinder wall 12 are closed by end plates (not shown), one of which may be made removable to gain access to the interior of the chamber. The interior of the chamber may either be under a vacuum or pressurized, depending on the type of process being carried out. In the usual circumstances, however, a pressure differential exists between the interior of the chamber and the surrounding exterior atmosphere.

In the arrangement herein schematically depicted, open width material, such as for example a cloth web 16 is being processed. The entering section 16a of the web is continuously directed over an idler roll 18 and then downwardly through an opening 20 at the top of the chamber 10. Once inside the chamber, the web material is threaded through a series of guide rolls generally indicated at 22 before being deposited in overlapping folds as at 161; on a horizontal roller conveyor 24. As the cloth reaches the end of the conveyor, it is directed upwardly and around another series of guide rolls generally indicated at 26 for exiting as at 160 from the chamber through opening 20. Once out of the chamber, the material continues on to the next processing step.

The cloth web can be subjected to any one of a number of treatments while moving through chamber 10. For example, a typical operation might involve bleaching or scouring at a chamber pressure and temperature of 30 p.s.i. and 273 F. respectively. Under these conditions, treatment time would run about -120 seconds.

The seal assembly which is the subject of the present invention is generally indicated at 28. Seal 28 effectively seals opening 20 and thus enables the interior of the chamber 10 to remain pressurized while the cloth web 16 continues to enter and exit from the chamber. The seal assembly 28 will not be described in greater detail by referring to FIGS. 2 and 3 wherein it can be seen that a generally rectangular plate 30 is secured to the chamber wall 12 by any known means such as a plurality of bolts indicated typically at 32. A groove 34 is machined into the under surface of the plate to accommodate a gasket 36 which is squeezed between the plate and chamber wall 12 when the bolts 32 are tightened. When thus secured, plate 30 becomes in effect an upward integral extension of chamber wall 12. Plate 30 is further provided with a central opening which again is a vertical continuation of the passageway or opening 20 through which material enters and exits from the chamber. The inner edge 31 of plate 30 bordering opening 20 is grooved as at 40 to form a cavity suitably dimensioned to receive and retain an endless inflatable element 42. Element 42 is inflated through a line 43 extending from a remote air pump or other appropriate conventional pressurizing means (not shown). Line 43 extends through the plate 30 to be connected to the inflatable element as at 43.

An intermediate member or center bar 44 is suspended from an overlying support 46. The center bar 44 is located in the middle of opening 20 and is preferably provided with curved sides44a and 44b and curved ends 440 and 44d. The ends and sides of the center bar are spaced inwardly from and parallel to the surrounding edges of the components through which opening 20 extends vertically.

As is best shown in FIG. 2, the ends of the overlying support 46 are secured by'means of pins 48 to upstanding bifurcated brackets 50, the latter in turn being secured to the chamber wall 12 by means of bolts or screws 52.

The incoming cloth web 16a passes downward through opening 20 between the curved side 44a of center bar 44 and the inflatable sealing element 42. After being processed in the treatment chamber, the exiting cloth web 16c again passes upwardly through opening 20 between the opposite curved side 4412 of the center bar and the other side of the sealing element. In the embodiment shown in FIGS. l-3, the inwardly protruding nose 56 on the inflatable sealing element is protected against wear by means of a pair of wear elements 58. A number of materials may be employed as wear elements. Two materials, namely Rulon (manufactured by the Dixon Corporation of Bristol, Rhode Island, USA.) and a double dutch twill weave 20 350-mesh stainless steel wire cloth are currently under consideration with the wire cloth showing the greatest promise for extended continuous operation.

As can be best seen by reference to FIGS. 2 and 3, a holding strip 60 is attached to one side of each wear element. A plurality of springs 62 connect the holding strips 60 to clips 64 which in turn engage bars 66 fixed relative to the chamber wall 12. The opposite sides of the wear elements are each prol0l025 00M vided holding strips 68 which are appropriately shaped to form clips engaging holding bars 70, the latter being mounted in fixed positions on plate 30. The dimensions of the wear elements are such that the springs 62 are under tension when the seal element 42 is inflated. This, when combined with the spreading action provided by holding strips 60 and 68, avoid wrinkling of the wear elements during operation of the apparatus.

An alternate embodiment of a means for protecting the inflatable sealing element against rapid wear is illustrated in FIG. 4, wherein it can be seen that a relatively narrow strip 72 of wear material has been molded into the inwardly protruding nose 56a of the inflatable seal element 42a. With this arrangement the wear material becomes an integral part of the inflatable sealing element and no separate wear element is required.

Having thus described the basic components of a seal assembly embodying the concepts of the present invention, its novel and advantageous features will now be reviewed briefly. To begin with, it should be noted that the present seal is simple in design, inexpensive to construct, and easy to assemble and disassemble when threading the cloth web through opening 20. The steps followed in disassembly are: (a) equalize pressure between the interior and exterior of chamber and deflate seal element 42; (b) disengage pins 48 and remove center bar 44. The opening 20 is now exposed, thus facilitating threading material into and out of the chamber, and also permitting quick replacement of the wear elements 58 as well as the inflatable seal element when such replacement is needed. Assembly of the seal is accomplished just as easily by reversing the foregoing steps.

it is also important to note that the present seal arrangement provides a continuous effective seal around the entire circumference of the opening 20. This is due to the fact that center bar 44 is suspended in the opening and completely surrounded by the inflatable sealing element 42. When element 42 is inflated, preferably to a pressure which is about p.s.i. above either the operating chamber pressure or the exterior atmospheric pressure, whichever is higher, the following sealing actions are established: (a) the seal nose 56 is pushed inwardly towards the sides and ends of center bar 44. As mentioned previously, this causes the material entering and leaving the chamber to be sealingly engaged on opposite sides by the wear element (which can either be a separate component or an integral part of the inflatable element) and the curved sides 44a and 44b of the center bar. At the same time, any side sections of the center bar 44 not covered by the entering and exiting web material, as well as the curved ends 44c and 44d, are also sealingly engaged by the inflated element 42. Thus, a complete continuous seal is established around the entire periphery of opening in the plane occupied by the inwardly disposed nose 56 of the inflatable sealing element 42.

The foregoing is accomplished quickly and easily without undue regard to the accurate placement and registration of removable seal components, such as the center bar 44. Slight variations of the vertical or horizontal positioning of the center bar will have little if any effect on the performance of the seal because the surrounding inflatable element 42 will readily compensate for such variations.

It should now be evident to those skilled in the art that the seal assembly described above can also be employed to seal an opening through which material passes in only one direction when either entering or leaving the treatment chamber. A typical illustration of this general arrangement which may be necessary when due to the design of the chamber, separate openings in the chamber wall are required to accommodate the entering and exiting material, is provided in FIG. 5 wherein it can be seen that an entering web i6a is sealingly engaged between the wear material 58 and one side 44a of center bar 44. The wear material is urged towards center bar 44 by the inflated element 42, which also sealingly engaged the Opposite side 44b and ends of the center bar, thus providing a complete seal for opening 20.

It is my intention to cover all changes and modifications of the invention herein chosen for purposes of disclosure which do not depart from the spirit and scope of the invention.

lclaim:

1. For use with a treatment chamber having an opening through which material passes continuously, a seal for said opening comprising: a stationary member spaced from the peripheral edge of said opening; inflatable sealing means extending inwardly from the edge of said opening towards said stationary member, said sealing means completely surrounding said stationary member with the said material passing between said sealing means and said stationary member; and, means for inflating said sealing means to an extent such that the space between said stationary member and the edge of said opening is effectively sealed, with the said material being sealingly engaged on opposite sides by said stationary member and said sealing means.

2. The apparatus as claimed in claim 1 wherein said inflatable sealing means is comprised of a single endless inflatable element.

3. The apparatus as claimed in claim 2 further characterized by element retaining means secured to the wall of the chamber, said element retaining means having a groove extending continuously around said opening, the said endless inflatable element being seated within said groove.

4. For use with a treatment chamber having an opening through which material passes continuously, a seal for said opening comprising: a stationary member surrounded by and laterally spaced from the peripheral edge of said opening; inflatable sealing means extending inwardly from the edge of said opening towards said stationary member, said sealing means completely surrounding said stationary member, a wear element covering at least a portion of said sealing means with the said material passing between said wear element and said stationary member; and, means for inflating said sealing means to an extent such that the space between said stationary member and the edge of said opening is effectively sealed, with the said material being sealingly engaged on opposite sides ofsaid stationary member and said wear element.

5. The apparatus as claimed in claim 4 wherein said wear element is comprised of a double dutch twill weave 20 350- mesh stainless steel wire cloth.

6. For use with a treatment chamber having an opening through which material continuously enters and leaves the chamber, a seal for said opening comprising: a stationary member spaced from the surrounding edge of said opening; inflatable sealing means extending inwardly from the edge of said opening towards said stationary member, said sealing means completely surrounding said stationary member, the material entering the chamber being passed between the sealing means and one side of said stationary member, and the material leaving the chamber being passed between said sealing means and the other side of said stationary member; and, means for inflating said sealing means to an extent that the space between said stationary member and the edge of said opening is effectively sealed, with the material entering and leaving said chamber being sealingly engaged on opposite sides ofsaid stationary member and said sealing means.

7. For use with a treatment chamber having an elongated opening through which open width material is passed when entering and leaving the chamber, a seal for said opening comprising; an endless inflatable element extending around the periphery ofsaid opening; an intermediate member suspended in said opening, the periphery of said intermediate member being spaced from and parallel to the periphery of said opening, the said intermediate member being completely surrounded by said inflatable element; a wear element covering said inflatable element; the material entering and leaving the treatment chamber being passed between said wear element and opposite sides respectively of said intermediate member; and means for inflating said inflatable element to an extent such that the space between said intermediate member and the periphery of said opening is effectively sealed, with the material entering and leaving the chamber being sealingly engaged between said wear element and said intermediate member.

8. A seal for an opening in a chamber through which open width material continuously enters and exits from said chamber, said seal comprising: a stationary member suspended in said opening, the periphery of said member being spaced from and parallel to the periphery of said opening; sealing means including an endless inflatable element coextensive with the periphery of said opening; a wear element covering said inflatable element; the material entering and leaving the chamber being passed between said wear element and opposite sides respectively of said stationary member, and, means for inflating said inflatable element to effectively seal any unoccupied space between the periphery of said opening and said stationary member.

9. For use with a treatment chamber, a seal for an opening in the chamber wall through which material is passed when entering and leaving the chamber, said seal comprising: element retaining means coextensive with the edges of said opening; an endless inflatable element supported by and coextensive with said retaining means; a stationary member suspended in said opening in a position surrounded by and spaced inwardly from said retaining means, the material entering said chamber being passed between said inflatable element and one side of said stationary member, with the material leaving said chamber being passed between said inflatable element and the opposite side of said stationary member; and, means for inflating said element to an extent such that the space between said stationary member and said retaining means is efiectively sealed, with the material entering and leaving the chamber being sealingly engaged on one side of said stationary member and on the other side of said inflatable element.

10. For use with a treatment chamber having an opening through which material is passed when entering and leaving the chamber, a seal for said opening comprising: inflatable sealing means coextensive with the edges of said opening; an intermediate'member suspended in said opening in a position surrounded by said inflatable sealing means, the material which enters said chamber being passed between said sealing means and one side of said intermediate member and the material leaving said chamber being passed between said sealing means and the opposite side of said intermediate member; and, means for inflating said sealing means, whereby any space between said intermediate member and said sealing means is effectively sealed, with the material entering and leaving said chamber being sealingly engaged between said intermediate member and said sealing means.

11. For use with a treatment chamber having an opening through which material is passed when entering and leaving the chamber, a seal for said opening comprising: inflatable sealing means coextensive with the edges of said opening; an intermediate member suspended in said opening in a position surrounded by said inflatable sealing means, wear element means covering at least a portion of said inflatable sealing means, the material which enters said chamber being passed between said wear element means and one side of said intermediate member and the material leaving said chamber being passed between said wear element means and the opposite side of said intermediate member; and, means for inflating said inflatable sealing means, whereby any space between said intermediate member and the edge of said opening is effectively sealed, with the material entering and leaving said chamber being sealingly engaged between said intermediate member and said wear element means.

12. The apparatus as claimed in claim 10 further characterized by the material-contacting portions of said inflatable sealing means having embedded therein wear resistant material.

13. The apparatus as claimed in claim 12 wherein said wear resistant material is comprised of a stainless steel wire mesh.

H025 (mm 

1. For use with a treatment chamber having an opening through which material passes continuously, a seal for said opening comprising: a stationary member spaced from the peripheral edge of said opening; inflatable sealing means extending inwardly from the edge of said opening towards said stationary member, said sealing means completely surrounding said stationary member with the said material passing between said sealing means and said stationary member; and, means for inflating said sealing means to an extent such that the space between said stationary member and the edge of said opening is effectively sealed, with the said material being sealingly engaged on opposite sides by said stationary member and said sealing means.
 2. The apparatus as claimed in claim 1 wherein said inflatable sealing means is comprised of a single endless inflatable element.
 3. The apparatus as claimed in claim 2 further characterized by element retaining means secured to the wall of the chamber, said element retaining means having a groove extending continuously around said opening, the said endless inflatable element being seated within said groove.
 4. For use with a treatment chamber having an opening through which material passes continuously, a seal for said opening comprising: a stationary member surrounded by and laterally spaced from the peripheral edge of said opening; inflatable sealing means extending inwardly from the edge of said opening towards said stationary member, said sealing means completely surrounding said stationary member, a wear element covering at least a poRtion of said sealing means with the said material passing between said wear element and said stationary member; and, means for inflating said sealing means to an extent such that the space between said stationary member and the edge of said opening is effectively sealed, with the said material being sealingly engaged on opposite sides of said stationary member and said wear element.
 5. The apparatus as claimed in claim 4 wherein said wear element is comprised of a double dutch twill weave 20 X 350-mesh stainless steel wire cloth.
 6. For use with a treatment chamber having an opening through which material continuously enters and leaves the chamber, a seal for said opening comprising: a stationary member spaced from the surrounding edge of said opening; inflatable sealing means extending inwardly from the edge of said opening towards said stationary member, said sealing means completely surrounding said stationary member, the material entering the chamber being passed between the sealing means and one side of said stationary member, and the material leaving the chamber being passed between said sealing means and the other side of said stationary member; and, means for inflating said sealing means to an extent that the space between said stationary member and the edge of said opening is effectively sealed, with the material entering and leaving said chamber being sealingly engaged on opposite sides of said stationary member and said sealing means.
 7. For use with a treatment chamber having an elongated opening through which open width material is passed when entering and leaving the chamber, a seal for said opening comprising; an endless inflatable element extending around the periphery of said opening; an intermediate member suspended in said opening, the periphery of said intermediate member being spaced from and parallel to the periphery of said opening, the said intermediate member being completely surrounded by said inflatable element; a wear element covering said inflatable element; the material entering and leaving the treatment chamber being passed between said wear element and opposite sides respectively of said intermediate member; and means for inflating said inflatable element to an extent such that the space between said intermediate member and the periphery of said opening is effectively sealed, with the material entering and leaving the chamber being sealingly engaged between said wear element and said intermediate member.
 8. A seal for an opening in a chamber through which open width material continuously enters and exits from said chamber, said seal comprising: a stationary member suspended in said opening, the periphery of said member being spaced from and parallel to the periphery of said opening; sealing means including an endless inflatable element coextensive with the periphery of said opening; a wear element covering said inflatable element; the material entering and leaving the chamber being passed between said wear element and opposite sides respectively of said stationary member, and, means for inflating said inflatable element to effectively seal any unoccupied space between the periphery of said opening and said stationary member.
 9. For use with a treatment chamber, a seal for an opening in the chamber wall through which material is passed when entering and leaving the chamber, said seal comprising: element retaining means coextensive with the edges of said opening; an endless inflatable element supported by and coextensive with said retaining means; a stationary member suspended in said opening in a position surrounded by and spaced inwardly from said retaining means, the material entering said chamber being passed between said inflatable element and one side of said stationary member, with the material leaving said chamber being passed between said inflatable element and the opposite side of said stationary member; and, means for inflating said element to an extent such that the space between said stationary member and said retaining means is effectively sealed, with the material entering and leaving the chamber being sealingly engaged on one side of said stationary member and on the other side of said inflatable element.
 10. For use with a treatment chamber having an opening through which material is passed when entering and leaving the chamber, a seal for said opening comprising: inflatable sealing means coextensive with the edges of said opening; an intermediate member suspended in said opening in a position surrounded by said inflatable sealing means, the material which enters said chamber being passed between said sealing means and one side of said intermediate member and the material leaving said chamber being passed between said sealing means and the opposite side of said intermediate member; and, means for inflating said sealing means, whereby any space between said intermediate member and said sealing means is effectively sealed, with the material entering and leaving said chamber being sealingly engaged between said intermediate member and said sealing means.
 11. For use with a treatment chamber having an opening through which material is passed when entering and leaving the chamber, a seal for said opening comprising: inflatable sealing means coextensive with the edges of said opening; an intermediate member suspended in said opening in a position surrounded by said inflatable sealing means, wear element means covering at least a portion of said inflatable sealing means, the material which enters said chamber being passed between said wear element means and one side of said intermediate member and the material leaving said chamber being passed between said wear element means and the opposite side of said intermediate member; and, means for inflating said inflatable sealing means, whereby any space between said intermediate member and the edge of said opening is effectively sealed, with the material entering and leaving said chamber being sealingly engaged between said intermediate member and said wear element means.
 12. The apparatus as claimed in claim 10 further characterized by the material-contacting portions of said inflatable sealing means having embedded therein wear resistant material.
 13. The apparatus as claimed in claim 12 wherein said wear resistant material is comprised of a stainless steel wire mesh. 